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81.
Investigation on ultrafast thrid—order optical nonlinearity of metal(dmit)2/mnt)2 Charge transfer complexes 下载免费PDF全文
We have investigated the transient third-order optical nonlinearity of the solutions of Metal(dmit)2/(mnt)2 salts in acetone by employing femtosecond optical Kerr gate measurement at 830nm wavelength.An order of enhancement on the second-order hyperppolarizability is found for the above salts with central atoms of Cu and Ni.We have suggested an explanation for the enhancement based on the extension of electronic conjugation by the entring Cu or Ni atom. 相似文献
82.
The K+−nucleus cross sections have been calculated in relativistic non-linear models taking into account the in-medium modifications of nucleons and mesons properties. More precisely, we have taken into account both the dressing of the nucleon effective mass by the scalar nuclear field in the target and the coupling of the mesons exchanged between the K+ and the nucleons to the polarization of the medium. First, using the most recent relativistic non-linear models, the in-medium σ, ω and ρ meson masses have been obtained in the nuclear matter rest frame. The influence of the non-linear contributions on the K+−nucleus cross sections has then been studied. Finally, we have compared our results with the experimental data. 相似文献
83.
84.
85.
The stability of regioregular poly(3-hexylthiophene 2,5-diyl) (P3HT) thin films sandwiched between indium tin oxide (ITO)
and aluminium (Al) electrodes have been investigated under normal environmental conditions (25°C and RH∼45–50%). Electrical
and optical properties of ITO/P3HT/Al devices have been studied over a period of 30 days. Mobility μ of the order of 10−4 cm2/V-s has been obtained from the V
2 law in the as-deposited P3HT films. Scanning electron microscopy (SEM) investigations show blistering of Al contacts in devices
with a poly(3,4-ethylenedioxythiophene) (PEDOT) interlayer on application of voltage whereas no blistering is seen in devices
without PEDOT. The results have been explained in terms of trap generation and propagation and the moisture-absorbing nature
of PEDOT.
相似文献
86.
87.
Brad M. Rosen Virgil Percec 《Journal of polymer science. Part A, Polymer chemistry》2007,45(21):4950-4964
Atom transfer radical polymerization (ATRP) and single electron‐transfer living radical polymerization (SET‐LRP) both utilize copper complexes of various oxidation states with N‐ligands to perform their respective activation and deactivation steps. Herein, we utilize DFT (B3YLP) methods to determine the preferred ligand‐binding geometries for Cu/N‐ligand complexes related to ATRP and SET‐LRP. We find that those ligands capable of achieving tetrahedral complexes with CuI and trigonal bipyramidal with axial halide complexes with [CuIIX]+ have higher energies of stabilization. We were able to correlate calculated preferential stabilization of [CuIIX]+ with those ligands that perform best in SET‐LRP. A crude calculation of energy of disproportionation revealed that the same preferential binding of [CuIIX]+ results in increased propensity for disproportionation. Finally, by examining the relative energies of the basic steps of ATRP and SET‐LRP, we were able to rationalize the transition from the ATRP mechanism to the SET‐LRP mechanism as we transition from typical nonpolar ATRP solvents to polar SET‐LRP solvents. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4950–4964, 2007 相似文献
88.
Meng F. Q. Lu M. K. Yang Z. H. Zeng H. 《Journal of Thermal Analysis and Calorimetry》1998,52(2):609-613
The thermal behavior of two new non-linear optical (NLO) materials, urea-(D) tartaric acid (UDT) and urea-(DL) tartaric acid
(UDLT) were studied by using DSC, TG and TMA. The results show that: 1) The two crystals have different melting points but
similar decomposition temperatures due to the influences of intermolecular forces, which is attributed to the stereo effects
of (D)-tartaric and (DL)-tartaric acid molecules; 2) There was only thermal expansion and no thermal contraction when the
UDT and UDLT crystals were heated; 3) There was no phase transition within the measured temperature range; 4) The thermal
expansion of the UDT and UDLT crystals shows a small anisotropy; 5) The specific heats of UDT and UDLT change linearly with
temperature in the measured temperature range and the value for UDT is 1.321 J g-1 K-1 at 320 K while the specific heat of
UDLT is 1.357 J g-1 K-1 at the same temperature.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
Summary The relative X-ray fluorescence (XRF) intensities for annular source and various annular specimen are measured with a Ge-Li
detection system and calculated by the Monte Carlo numerical techniques (MCNT).Kα X-ray intensities of annular specimens with different radii prepared from a pure-molybdenum foil are measured and it is
seen that the measured values are in good agreement with the values calculated by MCNT. The variation of the fluorescence
intensity due to the collimator radius is also studied. The differences between the MCNT and experimental results are discussed
in terms of the possible sources of errors. 相似文献
90.
N. V. Sotskaya O. V. Dolgikh E. I. Ryabinina 《Russian Journal of Electrochemistry》2005,41(8):866-873
The rate of anodic oxidation of the hypophosphite ion on alloys Ni-P, Ni-B, and Ni-Mo-P is studied as a function of their composition and structure. The organic compounds that are customarily used to stabilize electrolytes of electroless nickel plating are shown to come useful when controlling composition of the Ni-P coatings at the expense of their different influence on the rates of partial processes of deposition of the alloy components. The formation of catalytic activity of such coatings is affected mostly by a structural factor. With alloys Ni-P, Ni-B, and Ni-Mo-P, whose composition was varied by altering the concentration of the source of the alloying component, dependence of catalytic activity of the surface on the composition is defined mainly by an electronic factor.__________Translated from Elektrokhimiya, Vol. 41, No. 8, 2005, pp. 972–980.Original Russian Text Copyright © 2005 by Sotskaya, Dolgikh, Ryabinina. 相似文献